Immunoglobulin G4 associated autoimmune cholangitis and pancreatitis following the administration of nivolumab: A case report

Figure 1 Cholangiogram obtained via endoscopic retrograde cholangiopancreatography demonstrating a single localized biliary stricture within the distal common bile duct with upstream dilation.

Figure 2 Hematoxylin and eosin stained. A: Low power hematoxylin and eosin (H&E) showing marked chronic mixed cell infiltrates and fibrosis within epithelial and subepithelial region; B: Medium power H&E microscopy showing venules flanked by lymphocytes consistent with lymphocytic phlebitis (arrows); C: Medium power trichrome microscopy showing Prussian blue trichome staining of fibrosis with storiform pattern; D: High power H&E microscopy showing plasma call predominant inflammatory cell infiltrates amidst biliary glands; E: High power view of same area in D, showing numerous plasma cells highlighted with dark brown signal by CD138 immunohistochemistry antibody, a plasma cell biomarker; F: High power view of same area in D, showing numerous immunoglobulin G4 (IgG4) positive plasma cells highlighted with dark brown signals by IgG4 immunohistochemistry antibody.